sip trunk with CUCM

Dear experts,

I need to connect my CUCM 5.1 with sip proxy on telco side.IP phones
will connect to CUCM.
The SIP server provide 90 lines with real numbers

Following is the scenario.

Cisco IP phones----------CUCM-------WAN connection to
telco---------SIP proxy server.

Can anybody explain me how this will work, what will be the
configurations and if CUCM has the capability to control the calls
between IP phones and SIP server.

--
Thanks & Regards,
Asim Zafar
-- 
Thanks & Regards,
Asim Zafar
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